Technical Field
The present disclosure relates to image processors, and more particularly, to an image processor that compresses a still picture to be compressed in a block unit.
Related Art
In accordance with one technique, an image processor includes a compression unit that compresses an image to be compressed, a frame buffer for storing a compressed image compressed by the compression unit, and a decompression unit that decompresses a compressed image output from the frame buffer.
JP2009-212800A describes an image compression device that compresses an image to be compressed in a unit of a block having a predetermined number of pixels, employing Block Truncation Coding (BTC) compression.
Recent cameras and televisions have rapidly improved in resolution, which increases occasions to process images having a large number of pixels in image compression of still pictures. Processing an image to be compressed having a large number of pixels requires a large-capacity, high-bandwidth frame buffer, resulting in higher product cost. On the other hand, compression with excessively high compression ratio to reduce buffer capacity and data transfer rate leads to significant degradation in image quality.